Car is lean, timing is getting pulled, and EGT's are up, please help.

[killakev805]

Alright here is the rundown:

I recently ran 5 gal of c16 through my car, and then after that it was running fine. I then had to drive all the way to Lake Tahoe, (500 miles) and back(500 miles), everything was fine on the trip. After I get back home, now when I get in the throttle it runs great until it gets over 5k rpms, then it yanks my timing and the EGT's shoot through the roof. I am guessing that I am getting detonation but I am not sure what is causing it, I haven't changed anything, except I did put new plugs(bpr6es gapped at .028) and wires on last night, but that didn't help any. Also, it did throw a cel twice once before the c16 and once after. It was P0420 = Catalyst Efficiency below threshold (bank 1).

Any help would be appreciated.

My mods are in my profile, I am running 18psi on 91 pump gas.

 

[ozzeran]

Try this link:

http://www.obd-codes.com/trouble_codes/generic/p0430-catalyst-efficiency-below-threshold-bank-2.php



I am guessing you do not have a cat at all on the car? What I dont understand is the downstream o2 sensor shouldnt change the a/f mixture, at least that is what I heard. That is what the upstream one is for. So dunno if thats going to help you. But check those items out on that site and see if that helps.

 

[killakev805]

yeah, I don't think the cel issue is causing my problem, I think your correct, that the second o2 doesn't effect my a/f, and your correct about the cat.

I forgot to mention also, that now the fuel pump is a little louder than before. It is a walbro 190, so yes it did make some noise before, but it seems to have gotten louder. I also ran some sea-foam through the tank just in case I had some dirty injectors, but that had no effect either.

 

[ozzeran]

yeah, I don't think the cel issue is causing my problem, I think your correct, that the second o2 doesn't effect my a/f, and your correct about the cat.

I forgot to mention also, that now the fuel pump is a little louder than before. It is a walbro 190, so yes it did make some noise before, but it seems to have gotten louder. I also ran some sea-foam through the tank just in case I had some dirty injectors, but that had no effect either.

Have you replaced the fuel filter recently? If not it might be putting strain on the pump (maybe) Really dunno what to tell you, i'm just now starting to get into the problems these cars produce as mine is being dumb. Hope you get it fixed and make sure you and post the fix when you do